4.0Mm Min Bore Guhring Boring/Profiling Lh System 104 Insert, .015Mm (T-Max) Offset, 22Mm Reach, Tin Coated Left Hand, 0.05Mm Radius, Tin Coated Gt104.0837.005.22.40.L, Tin Coated Type Gt104 Guhring Micro-Precision System 104 Carbide Stick Insert With 4Mm Quick Change Shank For Boring & Profiling. Guhring Series No. 25083 Order Code 4.015 Made In Germany, Guhring Part #9250830040150 Guhring Inc.